PMS - a week and a bit early?

Hi! :hello:This is my first post here, but I have been a regular lurker for awhile and have found so many posts very helpful.
I am currently on CD 18 and as far as I can tell 3 DPO, FH and I aren't officially trying, yet - I have just been trying to get as much info as I can and understand what goes on with my body so we can be prepared after we marry.
For the last two and a bit days, though, I have been feeling really emotional. I'll cry at the drop of a hat and my boyfriend said last night I am acting like I have PMS but we both know I'm not due yet (he has a program on his phone that warns him and is amazingly acurate). I have not just come off the pill, which would be a good explaination!!
I've had pains which I figured were Ovulations pains, but no CM to speak of.
Generally my cycles are 27 - 30 days. I'm just wondering if it's normal to get PMS so early? Or is it possible I ovulated early and that's why I had no CM when I thought I should?

Thanks in advance and I hope it all makes sense

LOL @ your BF programming your PMS into his phone. That's a riot!!

So... you've just come off the pill? Did I read that right?? That'll do it to you. I know my first cycle off the pill was a bit all over the shop.

Otherwise (even though you're not TTC yet), when you are in the "baby" frame of mind, you tend to over analyse every single little symptom because you're listening to your body more. Maybe a little bit of that is happening??

It's always funny when I cry and he checks his phone and is like "Yup, it's a blue dot day."

No, sorry if that was unclear, I haven't just come off the pill.

Maybe there is a bit of that over-analysing going on, though I don't think for a second that I am pregnant. I just don't normally cry so much or get so sensitive unless I am PMSing. Do you think it's possible to be pre menstral so early?
And I am curious as to why I have had no CM. I normally do get quite a bit.
Anyway, thanks :)